Lateral lumbar interbody fusion via a unilateral true percutaneous approach associated with minimally invasive pedicle screw fixation for degenerative disc disease and lumbar instability. A technical note.

In recent years, minimally invasive surgical techniques for lumbar fusion and fixation procedures gained worldwide popularity. Herein we describe a personal technique for percutaneous lumbar interbody fusion associated with minimally invasive posterior fixation for patients affected by degenerative disc disease and lumbar instability. The procedure is described in a step-by-step way and early results are presented. Although the present data reflect only an early experience, we believe that this is a straightforward procedure which may be more advantageous in terms of surgical invasiveness, potentially saving operative and recovery time and reducing risks compared to posterior or anterior approaches for lumbar interbody fusion.

Lack of correlation between Ki-67 labelling index and tumor size of anterior pituitary adenomas.

AIMS AND BACKGROUND: The Ki-67 is a nuclear antigen detected by the monoclonal antibody MIB-1 and its Labeling Index (LI) is considered a marker of normal and abnormal cell proliferation. Pituitary adenomas are generally well differentiated neoplasms, even if in about one third of cases they are invasive of surrounding tissues. The aim of this study is to evaluate the correlation between Ki-67 labelling index and tumor size of pituitary adenomas extimated by means CT and MRI and confirmed at operation. METHODS: Using the monoclonal antibody MIB-1, we evaluated the expression of Ki-67 in 121 anterior pituitary adenomas consecutively operated on in a 48-month period. RESULTS: In relation to neuroradiological (CT and MRI) and surgically verified tumor size, we identified 24 microadenomas, 27 intrasellar macroadenomas, 34 intra-suprasellar macroadenomas, and 36 intra-supra-parasellar macroadenomas. The adenomas were non-infiltrating (76 cases) and infiltrating (45 cases) adenomas. The wall of the cavernous sinus (CS) was infiltrated in 18 cases. Forty-eight adenomas were non-functioning and 73 functioning. The overall mean +/- SD Ki-67 LI was 2.72 +/- 2.49% (median 1.6). It was 2.59 +/- 1.81 in microadenomas, 2.63 +/- 3.45 in intrasellar macroadenomas, 1.91 +/- 2.11 in intra-suprasellar macroadenomas, and 3.29 +/- 5.45 in intra-supra-parasellar macroadenomas (p = 0.27). It was 3.73 +/- 5.13% in infiltrating and 2.03 +/- 2.41% in non-infiltrating adenomas (p = 0.02), and 5.61 +/- 7.19% in CS-infiltrating versus 2.09 +/- 2.37% in CS-non-infiltrating adenomas (p = 0.0005). CONCLUSIONS: Our preliminary results seem to exclude significative correlations between Ki-67 LI and tumor size of anterior pituitary adenomas, even if this index can be considered a useful marker in the determination of the infiltrative behaviour of these tumors.

Relationships among DNA Index, S-Phase, and invasive behavior in anterior pituitary adenomas. A cytometric study of 61 cases with Feulgen-positive DNA analysis.

BACKGROUND: Pituitary adenomas are usually well differentiated neoplasms, although in about 1/3 of cases they invade the surrounding dura mater and bone, as confirmed by surgical findings, resulting in a long-term possibility of relapse. METHODS: To identify the cellular growth rate and to correlate it with surgical evidence of invasiveness, we performed the analysis of DNA with static cytometric quantitation on fresh surgical specimens, using a computer-assisted image processor. The DNA index and the percentage of cells in S-phase (%SPh) were obtained in 61 pituitary tumors consecutively operated on. In relation to surgically verified infiltration of dura and bone, we identified 39 noninvasive and 22 invasive adenomas. The cavernous sinus (CS) was infiltrated in 13 cases. On the basis of immunohistochemical staining and endocrine activity we recognized 27 nonsecreting and 34 secreting adenomas. RESULTS: The DNA content was aneuploid in 33 cases (11 nonfunctioning, 22 functioning; p = 0.05); there was no correlation with the invasive behavior of the adenomas. The DNA index ranged between 0.93 and 2.50 (median 1.13); the range of %SPh was 0-12.00% (median 2.54%). In invasive adenomas the mean DNA index was 1.33 (p not significant) and the mean %SPh was 4.03% (p = 0.05). In CS-infiltrating pituitary adenomas, the mean DNA index was 1.44 (p = 0.04) and the mean %SPh was 4.52% (p = 0.05). CONCLUSIONS: Our preliminary results seem to reveal a correlation between DNA index, %SPh, and invasive behavior of pituitary adenomas, encouraging the use of DNA analysis in the prognostic evaluation of these tumors.

Proposal of a clinico-histological "glioma score" as a prognostic index in high-grade glioma patients. Preliminary observations in a series of 80 cases.

BACKGROUND: Despite of several multimodal treatments, malignant gliomas still have a poor outcome. In order to identify subgroups of patients with different prognosis, we propose a clinical and histological score (GS). METHODS: Eighty consecutive patients operated on for a high-grade glioma and treated with adjuvant therapy entered the study. In relation to age at diagnosis, preoperative Karnofsky Performance Status (KPS), and MIB-1 index, patients have been splitted in 4 groups (GS 0-III). RESULTS: The overall mean survival of the entire cohort was 18.2 months (median 12). Patients with GS 0 have a mean survival rate of 30.0 months, with GS I 23.1 months, with GS II 12.1 months, and with GS III 9.0 months (p=0.0001). Moreover, mean survival with a KPS = or >70 was 29.0 in GS 0, 26.0 in GS I, 10.0 in GS II, and 0 in GS III patients (p<0.0001). CONCLUSIONS: On the basis of these preliminary observations, we discuss the utility of our "glioma score" as a prognostic indicator for patients operated on for cerebral malignant gliomas and treated postoperatively with adjuvant therapy.

Adrenocorticotropic hormone secreting pituitary adenomas: analysis of growth fraction using the MIB-1 antibody.

AIMS AND BACKGROUND: Pituitary adenomas are usually considered well differentiated tumors, even if in about one third of cases they invade surrounding tissues, with the possibility of postoperative relapse after complete surgical removal. Adrenocorticotropic hormone (ACTH) secreting adenomas seem to be the most infiltrating subtype, with a higher incidence of recurrence. Ki-67 is a nuclear antigen which is easily detectable by means of the MIB-1 monoclonal antibody, and the labeling index (LI) obtained can be considered a marker of tumor proliferation. METHODS: In order to identify the growth fraction of these tumors we used the MIB-1 antibody to evaluate the expression of Ki-67 antibody in 11 ACTH secreting pituitary adenomas and to compare it with the LI obtained in 98 other hormone secreting or non-functioning pituitary adenomas consecutively operated on during a 40-month period. RESULTS: In relation to surgically verified infiltration of the sellar floor dura and bone, we identified eight non-invasive and three invasive ACTH secreting pituitary adenomas. All invasive tumors infiltrated the wall of the cavernous sinus (CS). The mean Ki-67 LI was 5.88 +/- 9.13% versus 2.33 +/- 2.40% in non-ACTH secreting adenomas (P = 0.0025). It was 13.27 +/- 15.42% in invasive and 3.11 +/- 4.37% in non-invasive ACTH adenomas, and 18.40 +/- 17.82% in patients over 50 years versus 3.10 +/- 4.09% in younger subjects (P = 0.02). CONCLUSIONS: Ki-67 LI is a useful marker in the determination of proliferative activity and invasiveness of anterior pituitary adenomas. Our data seem to confirm that ACTH secreting adenomas have a higher growth fraction than other pituitary adenomas and this observation presumably explains the higher incidence of relapse of these tumors even after macroscopically total removal.

Pupillary enlargement caused by an acute extradural haematoma associated with a non-symptomatic arachnoid cyst, from compression of the optic rather than the oculomotor nerve.

We report the case of an anisocoric boy with a posttraumatic left frontal-temporal extradural haematoma associated with a previously asymptomatic arachnoid cyst of the left anterior and middle fossa. Usually, anisocoria after a head injury suggests a third nerve palsy caused by an uncal herniation. In our case, the pupillary enlargement appeared to be caused by indirect compression of the optic nerve by the extradural haematoma, because of the low resistance exerted by the middle fossa arachnoid cyst.

Magnetic resonance imaging findings of Kernohan-Woltman notch in acute subdural hematoma.

OBJECTIVE AND IMPORTANCE: We report the case of a 73-year-old patient who presented a right motor deficit caused by an ipsilateral acute subdural hematoma. A magnetic resonance imaging (MRI) demonstration of Kernohan-Woltman notch phenomenon was obtained. CLINICAL PRESENTATION: The woman sustained a major head injury at home, followed by loss of consciousness. On admission to the emergency room, she was comatose, anisochoric (left > right), and showed a reaction to pain with decerebrating movements of left limbs (Glasgow Coma Scale (GCS) 4/15). A right severe hemiparesis was observed. Cerebral computed tomography scan showed a large right hemispheric subdural hematoma. INTERVENTION AND POST-OPERATIVE COURSE: A wide right craniotomy was performed and the subdural hematoma evacuated. During the post-operative period, the level of consciousness gradually improved. A MRI performed about 2 weeks after operation showed a small area of abnormal signal intensity in the left cerebral peduncle. On discharge, the woman was able to communicate with others, but her right hemiparesis was still severe.

Ki-67 labelling index and invasiveness among anterior pituitary adenomas: analysis of 103 cases using the MIB-1 monoclonal antibody.

AIMS: To investigate the relation between proliferative activity of anterior pituitary adenomas, quantified by the Ki-67 labelling index, and their invasive behaviour. METHODS: Expression of Ki-67 was evaluated in 103 anterior pituitary adenomas consecutively operated on in a 36 month period and correlated with surgical evidence of invasiveness. RESULTS: Non-invasive (n = 65) and invasive (n = 38) adenomas were identified from surgically verified infiltration of sellar floor dura and bone. The wall of the cavernous sinus was infiltrated in 16 cases. Forty one adenomas were non-functioning and 62 functioning (24 prolactin, 21 growth hormone, 10 ACTH, seven mixed). The overall mean (SD) Ki-67 labelling index was 2.64 (3.69) per cent (median 1.5). The mean index was 3.08 (4.59) per cent in functioning and 1.97 (1.78) per cent in non-functioning tumours; 5.47 (9.52) per cent in ACTH adenomas and 2.33 (2.42) per cent in others (p = 0.01); 3.71 (5.17) per cent in invasive and 2.01 (2.45) per cent in non-invasive adenomas (p = 0.027); and 5.58 (7.24) per cent in cavernous sinus infiltrating v 2.10 (2.39) per cent in cavernous sinus non-infiltrating adenomas (p = 0.0005). To identify a value of labelling index beyond which adenomas should be considered invasive and another beyond which cavernous sinus infiltration should be suspected, normality Q-Q plots were obtained: a threshold labelling index of 3.5% for invasive adenomas and of 5% for cavernous sinus infiltrating adenomas was defined, with statistically significant differences (p = 0.02 and p = 0.004, respectively). CONCLUSIONS: The Ki-67 labelling index can be considered a useful marker in determining the invasive behaviour of anterior pituitary adenomas.

Relationship between Ki-67 labeling index and survival in high-grade glioma patients treated after surgery with tamoxifen.

BACKGROUND: The Ki-67 is a nuclear antigen expressed in the G1, S, G2, and M phases of the cell cycle recognizable by the monoclonal antibody MIB-1. The Ki-67 labeling index (LI) is considered as a marker of proliferation (growth fraction rate), even if its use as prognostic indicator of cerebral high-grade gliomas is still debated. The aim of this study is to correlate the Ki-67 LI with survival in patients operated on for a malignant glioma and treated postoperatively with tamoxifen. METHODS: Using the MIB-1 antibody, the Ki-67 antigen staining of surgical specimens was obtained in 26 patients operated on for a malignant cerebral glioma. After operation, 9 patients started to receive 40 mg/day, 8 patients 80 mg/day, and 9 patients 120 mg/day of tamoxifen. In 20 cases one or more cycles of i.v. carboplatin was administered. All patients received radiotherapy (4500-6000 cGy). RESULTS: The overall mean survival rate was 19.8 months and the median 12 months; the 12-month and 24-month survival rates were 47% and 23%, respectively. The Ki-67 LI ranged from 2.3% to 62% (mean 24.1%, median 20.5%). Excluding 2 patients who died during the postoperative period, we analyzed the survival rates of the remaining 24 patients in relation to the value of Ki-67 LI. In relation to the index, patients have been divided into 3 groups, with different survival rates: L) Ki-67 LI < or =10%, with mean survival rate of 30.7 months, M) from 10.1% to 30%, with mean survival rate of 15.8 months, and H) >30%, with mean survival rate of 20.2 months. CONCLUSIONS: Our preliminary observations seem to confirm the efficacy of TAM in modifying the survival of malignant gliomas and seem to indicate that tumors with a lower LI and those with a LI >30% could be associated, if treated with TAM, with a better survival than gliomas belonging to group M, who could have a higher tumor proliferation rate in comparison to group L and a lower response to protein-kinase-C antagonists than group H.

Malignant cerebellar astrocytomas: clinico-pathological remarks on 10 cases.

BACKGROUND: Malignant glioma represent the 3rd¿4th most frequent cause of death from cancer. The cerebellar site is rare and life expectancy with cerebellar anaplastic astrocytoma is still dismall. The growth and clinical-pathological remarks of the tumor, is similar to the others gliomas of the central nervous system. MRI with Gd is the most useful diagnostic approach but lacks of specificity in detecting highly differentiated neoplasia areas. METHODS: Between 1980 and 1994 10 cases of malignant cerebellar astrocytomas were operated at the Neurosurgical Institute, Department of NeuroSciences, of Roma "La Sapienza" University. All patients were investigated pre-and postoperatively by CT scan with i.v. administration and/or MRI with Gd when possible. RESULTS: Of the 10 patients who followed various protocols, 7 died. Average survival was 13.7 months (range 5-21 months). 3 patients were still alive 12, 15 and 18 months after surgery. In 3 cases (50%) there was also radiological evidence of spinal cord spreading. CONCLUSIONS: Like cerebral lesions, malignant cerebellar astrocytoma still a pathology with a real unsatisfactory prognosis. Our experience probably showed that spinal spreading is underestimated. For this reason we believe that, despite the limited number of cases treated so far, it is important to extend postoperatively the radiotherapy to the entire spinal cord in all patients.

Anterior clinoidal meningiomas: report of a series of 33 patients operated on through the pterional approach.

Between 1985 and 1995, 33 cases of clinoidal meningioma were surgically treated by pterional approach. In 6 cases, according to the grading scale of Al-Mefty, the lesions were group I, having originated from the lower part of the clinoid; in 22 cases, the lesions were group II, having originated from the upper or lateral part of the clinoid process; and in 5 cases, the lesions were group III since they arose from the optic foramen. Postoperatively, 17 patients showed an improvement, 4 were unchanged, and 6 presented further deficits. Five patients died after surgery: two from pulmonary thromboembolism, one from myocardial infarction, one from hematoma of the operative field, and one from cerebral ischemia after severe vasospasm of the internal carotid artery (unresponsive to treatment). The mean follow-up was 53.7 months (range 12-108 months) and included 19 patients. During this period, there were five recurrences, and three patients underwent resection again and showed no signs of tumor regrowth 1 year later; one patient who did not undergo resection again due to his age and poor general conditions died 3 years after onset of the recurrence; the last patient has so far refused a second operation. The clinical, diagnostic, and therapeutic aspects of this not infrequent pathology are discussed in the light of our experience and the pertinent literature.

Intramedullary increased MR signal intensity and its relation to clinical features in cervical myelopathy.

BACKGROUND: Areas of intramedullary hyperintensity in patients with cervical spondylogenetic myelopathy (CSM) have been described and studied by several authors. METHODS: In the present study, 100 patients were reappraised and divided into 2 groups according to whether or not MRI detected areas of hyperintensity on T2-weighted images. RESULTS: Statistical analysis demonstrated that intramedullary hyperintensity is most frequently associated with severe impairment of deambulation, muscular hypotonus-hypotrophy and hypoesthesias of the upper limbs. CONCLUSIONS: These radiological findings probably correspond to various types of lesions which, when irreversible, may influence postoperative neurological recovery.

The role of MRI in the surgical selection of cerebral metastases.

BACKGROUND: About one third of patients operated on for a "single" cerebral metastasis diagnosed by CT scan have probably more than one lesion. In fact, Gd-DTPA enhanced MRI has proved to be more sensitive than CT in detecting the number of cerebral metastases, reducing the number of patients candidate to surgery. METHODS: Thirty-five patients with a CT scan picture of a single cerebral neoplasm of presumable metastatic nature performed a Gd-DTPA enhanced cerebral MRI. In 25 cases MR images confirmed a single lesion, while in other 10 (28.6%) showed a number of metastases ranging from 2 to 6. In order to assess the utility of MRI in surgical selection of patients and then to reconsider the concept of operability limited to single brain metastases only, we compared the survival of the 25 cases who preoperatively performed MRI (MRI group) with that of other 25 consecutive patients operated on in pre-MR era (during a 24-month period), with a CT picture of single cerebral metastasis (non-MRI group). RESULTS: The median survival was 36 +/- 5 weeks for MRI group and 40 +/- 15 for non-MRI group. The Kaplan-Meier product-limit survival analysis and the log-rank test do not reveal any statistically significative difference of survival between the two groups. CONCLUSIONS: Even if the number of patients is limited for definitive considerations, our preliminary results seem to suggest that the further selection of surgical cases obtained with MRI could not impact significatively the survival. Therefore, in selected patients with multiple cerebral metastases a surgical treatment could be reasonable.

Glossopharyngeal nerve schwannoma: report of a case operated on by the far-lateral transcondylar approach.

Complete resection with conservation of cranial nerves is the primary goal of contemporary surgery for lower cranial nerve tumors. We describe the case of a patient with a schwannoma of the left glossopharyngeal nerve, operated on in our Neurosurgical Unit. The far lateral approach combined with laminectomy of the posterior arch of C1 was done in two steps. The procedure allowed total tumor resection and was found to be better than classic unilateral suboccipital or combined supra- and infratentorial approaches. The advantages and disadvantages of the far lateral transcondylar approach, compared to the other more common approaches, are discussed.

Metastatic spinal cord compression. Clinical remarks.

BACKGROUND: Metastatic compression of the spinal cord is a frequent occurrence throughout the evolution of neoplastic disease. Possible clinical-diagnostic strategies and therapeutic management of this pathology are discussed in terms of survival and quality of life. METHODS: The study includes 59 patients (40 males and 19 females, with an average age of 48.4 years) with metastatic spinal compression treated surgically in our centre (in some cases with stabilization of the spinal segment involved). RESULTS: In 40 cases the localization of the primary tumor was known when the patient was admitted. The segment involved was the dorsal one in 41 cases. The most frequent type of tumor was pulmonary carcinoma in males and breast carcinoma in females. Average survival was 5.3 months. Treatment integrated by stabilization improved the quality of life in comparison to laminectomy alone. Survival was also influenced by the histological type and site of the primary tumor. CONCLUSIONS: Surgical treatment not only prolongs survival but, above-all, guarantees a satisfactory quality of life.

Intracranial actinomycosis in juvenile patients. Case report and review of the literature.

A case of actinomycotic brain infection in a juvenile patient is described. Cases of actinomycosis affecting the head and neck are rare, particularly in juvenile patients. In this case complete resolution of the infection was achieved by means of surgical treatment and prolonged antibiotic therapy. The authors emphasize the importance of a combined approach for treatment of this unusual brain infection and stress the difficulties involved in the diagnosis of this pathology.

Early surgical treatment of intracerebral hemorrhages caused by AVM: our experience in 10 cases.

Between February, 1980, and April, 1993. 10 patients with intraparenchymal hemorrhage due to the bleeding of an arteriovenous malformation (AVM) underwent emergency surgical procedures within an average time of 3 hours (min. 2-max. 7) from casualty to admission. Rapid neurological worsening and mass effect of the extensive intracerebral hemorrhage prompted early surgical treatment. Post-operative angiography was performed to confirm that the malformation had been excluded from the circulation. The aim of this study is to evaluate the role of early surgery in patients requiring emergency surgical procedures for severe neurological injury induced by extensive intracerebral hematoma produced by AVM bleeding.